Shelf with integrated electronics

ABSTRACT

Inventory locations such as shelves in a materials handling facility may be used to store items of various shapes and sizes. Described is an inventory location that houses onboard electronics such as sensors to acquire sensor data and computing devices to process the sensor data. The sensors may include one or more weight sensors, position encoders for auto-facing units, and so forth. The inventory location includes features to protect the onboard electronics and facilitate physical reconfiguration to support products of different shapes and sizes.

BACKGROUND

Retailers, wholesalers, and other product distributors typicallymaintain an inventory of various items that may be ordered, purchased,leased, borrowed, rented, viewed, and so forth, by clients or customers.For example, an e-commerce website may maintain inventory in afulfillment center. When a customer orders an item, the item is pickedfrom inventory, routed to a packing station, packed, and shipped to thecustomer. Likewise, physical stores maintain inventory in customeraccessible areas, such as in a shopping area, and customers can pickitems from inventory and take them to a cashier for purchase, rental,and so forth.

Many physical stores also maintain inventory in a storage area,fulfillment center, or other facility that can be used to replenishinventory located in the shopping areas or to satisfy orders for itemsthat are placed through other channels (e.g., e-commerce). Otherexamples of entities that maintain facilities holding inventory includelibraries, museums, rental centers, and so forth. In each instance, foran item to be moved from one location to another, it is picked from itscurrent location and transitioned to a new location. It is oftendesirable to monitor quantity of inventory within the facility.

BRIEF DESCRIPTION OF FIGURES

The detailed description is set forth with reference to the accompanyingfigures. In the figures, the left-most digit(s) of a reference numberidentifies the figure in which the reference number first appears. Theuse of the same reference numbers in different figures indicates similaror identical items or features.

FIG. 1 is a block diagram illustrating a materials handling facility(facility) using a modular item stowage system using modular elementscoupled to platforms, according to some implementations.

FIG. 2 is a block diagram illustrating additional details of thefacility, according to some implementations.

FIG. 3 is a block diagram of a server configured to support operation ofthe facility, according to some implementations.

FIG. 4 illustrates a side view of an inventory location comprising theplatforms, according to some implementations.

FIG. 5 illustrates top views of a platform before and after mounting ofmodular elements including instrumented auto-facing units, dividers, andspacers, according to some implementations.

FIG. 6 illustrates a side view of the platform along line A-A depictingvarious features of the platform including a cable recess, according tosome implementations.

FIG. 7 illustrates a side view of the platform along line B-B depictingvarious features of the platform including weight sensors, according tosome implementations.

FIG. 8 illustrates top views of an instrumented auto-facing unit,according to some implementations.

FIG. 9 illustrates side views of the instrumented auto-facing unit,according to some implementations.

FIG. 10 illustrates a side view of a portion of the instrumentedauto-facing unit, according to some implementations.

While implementations are described herein by way of example, thoseskilled in the art will recognize that the implementations are notlimited to the examples or figures described. It should be understoodthat the figures and detailed description thereto are not intended tolimit implementations to the particular form disclosed but, on thecontrary, the intention is to cover all modifications, equivalents, andalternatives falling within the spirit and scope as defined by theappended claims. The headings used herein are for organizationalpurposes only and are not meant to be used to limit the scope of thedescription or the claims. As used throughout this application, the word“may” is used in a permissive sense (i.e., meaning having the potentialto), rather than the mandatory sense (i.e., meaning must). Similarly,the words “include,” “including,” and “includes” mean including, but notlimited to.

DETAILED DESCRIPTION

This disclosure describes a modular item stowage system and associatedmodular elements that provide inventory locations. These inventorylocations facilitate stowage of items at a materials handling facility(facility) or other setting. The facility may include, or have accessto, an inventory management system. The inventory management system maybe configured to maintain information about items, users, condition ofthe facility, and so forth. For example, the inventory management systemmay maintain data indicative of a number of items at a particularinventory location, what items a particular user is ordered to pick, howmany items have been picked or placed at the inventory location,requests for assistance, environmental status of the facility, and soforth. Operation of the facility may be facilitated by using one or moresensors to acquire information about interactions in the facility.Interactions may comprise the user picking an item from an inventorylocation, placing an item at an inventory location, touching an item,bringing an object such as a hand or face close to an item, and soforth. For example, the inventory management system may use interactiondata that indicates what item a user picked from a particular inventorylocation to adjust the count of inventory stowed at the particularinventory location.

Described in this disclosure is a modular item stowage system thatincludes devices for stowing and facilitating stowage of items. Aplatform is described that may be mounted to a support structure such asa counter, upright rack, and so forth. The platform provides physicalsupport and functional support operation of one or more modularelements. The platform may include various sensors to provide sensordata to the inventory management system. For example, the platform mayinclude a plurality of weight sensors to generate weight data about aload on the platform. For example, the load may comprise one or moreitems. The platform may also include electronics to receive data fromthe modular elements. The modular elements may include electronics toprovide sensor data, such as instrumented auto-facing units (AFUs).

Instrumented and uninstrumented AFUs may hold one or more items. The AFUmay include a sled that is under tension from a spring to push itemstowards a front of the AFU, where it is readily accessible to a user. Inthe instrumented AFU, a linear position sensor may report sensor dataindicative of the position of the sled, such as how close the sled is tothe front of the instrumented AFU. Using the sensor data indicative ofthe position, assuming items in the same instrumented AFU have the samedepth, and given information about the depth of a single product, aquantity of items in the instrumented AFU may be determined. Based on achange in quantity from a first time to a second time, a quantity ofitems that have been picked from or placed to the instrumented AFU maybe determined. This information may be used by the inventory managementsystem to operate the facility.

Other modular elements may contain no electronics but support stowage ofthe items. The modular elements may include dividers, spacers, hangers,bins, and so forth. The dividers may comprise a vertical member of wallthat maintains separation between different types of items that may beadjacent to one another on the platform. The spacers may comprisesurfaces that provide horizontal distance between other modular elementssuch as dividers and AFUs. For example, a wide item may extend from afirst modular element over a spacer. The hangers may provide pegs,hooks, or other structures from which items may hang. The bins maycontain compartments or recesses within which items may be stowed.

By using the devices and techniques described herein, operation of thefacility may be improved. The modular item stowage system may be easilyreconfigured to hold items in a desired configuration. For example, anoperator of the facility may easily reconfigure the AFUs, spacers,dividers, and so forth, on one or more platforms to arrange items toconform to a desired planogram that specifies how items are to bearranged in the inventory locations of the facility. Sensors on theplatform, sensors on the modular elements such as the instrumented AFUs,or other sensors in the facility provide sensor data that may be used bythe inventory management system to determine quantity on hand at aparticular inventory location, quantity picked or placed by the user,and so forth.

Illustrative System

An implementation of a materials handling system 100 configured to storeand manage inventory items is illustrated in FIG. 1. A materialshandling facility 102 (facility) comprises one or more physicalstructures or areas within which one or more items 104(1), 104(2), . . ., 104(Q) may be held. As used in this disclosure, letters in parenthesissuch as “(Q)” indicate an integer value greater than or equal to zero.The items 104 comprise physical goods, such as books, pharmaceuticals,repair parts, electronic gear, and so forth.

The facility 102 may include one or more areas designated for differentfunctions with regard to inventory handling. In this illustration, thefacility 102 includes a receiving area 106, a storage area 108, and atransition area 110.

The receiving area 106 may be configured to accept items 104, such asfrom suppliers, for intake into the facility 102. For example, thereceiving area 106 may include a loading dock at which trucks or otherfreight conveyances unload the items 104.

The storage area 108 is configured to store the items 104. The storagearea 108 may be arranged in various physical configurations. In oneimplementation, the storage area 108 may include one or more aisles 112.The aisle 112 may be configured with, or defined by, inventory locations114 on one or both sides of the aisle 112. The inventory locations 114may include one or more of shelves, racks, cases, cabinets, bins, floorlocations, or other suitable storage mechanisms for holding, supporting,or storing the items 104. The inventory locations 114 may be affixed tothe floor or another portion of the facility's 102 structure. Theinventory locations 114 may also be movable such that the arrangementsof aisles 112 may be reconfigurable. In some implementations, theinventory locations 114 may be configured to move independently of anoutside operator. For example, the inventory locations 114 may comprisea rack with a power source and a motor, operable by a computing deviceto allow the rack to move from one location within the facility 102 toanother.

One or more users 116(1), 116(2), . . . , 116(U) and totes 118(1),118(2), . . . , 118(T) or other material handling apparatuses may movewithin the facility 102. For example, the user 116 may move about withinthe facility 102 to pick or place the items 104 in various inventorylocations 114, placing them on the tote 118 for ease of transport. Thetote 118 is configured to carry or otherwise transport one or more items104. For example, the tote 118 may include a basket, cart, bag, bin, andso forth. In other implementations, other material handling apparatusessuch as robots, forklifts, cranes, aerial drones, and so forth, may moveabout the facility 102 picking, placing, or otherwise moving the items104. For example, a robot may pick an item 104 from a first inventorylocation 114(1) and move the item 104 to a second inventory location114(2).

One or more sensors 120 may be configured to acquire information in thefacility 102. The sensors 120 may include, but are not limited to,optical sensors, cameras, three-dimensional (3D) sensors, weightsensors, radio frequency (RF) receivers, temperature sensors, humiditysensors, vibration sensors, and so forth. The sensors 120 may bestationary or mobile, relative to the facility 102. For example, theinventory locations 114 may contain cameras configured to acquire imagesof picking or placement of items 104 on shelves, of users 116 in thefacility 102, and so forth. In another example, the floor of thefacility 102 may include weight sensors configured to determine a weightof objects thereupon. The sensors 120 are discussed in more detail belowwith regard to FIG. 2.

While the storage area 108 is depicted as having one or more aisles 112,inventory locations 114 storing the items 104, sensors 120, and soforth, it is understood that the receiving area 106, the transition area110, or other areas of the facility 102 may be similarly equipped.Furthermore, the arrangement of the various areas within the facility102 is depicted functionally rather than schematically. For example, insome implementations, multiple different receiving areas 106, storageareas 108, and transition areas 110 may be interspersed rather thansegregated in the facility 102.

The facility 102 may include, or be coupled to, an inventory managementsystem 122. The inventory management system 122 is configured tointeract with users 116 or devices such as sensors 120, robots, materialhandling equipment, computing devices, and so forth, in one or more ofthe receiving area 106, the storage area 108, or the transition area110.

During operation of the facility 102, the sensors 120 may be configuredto provide information suitable for tracking the location of objectswithin the facility 102, their movement, and so forth. For example, aseries of images acquired by the camera may indicate removal of an item104 from a particular inventory location 114 by the user 116 andplacement of the item 104 on or at least partially within the tote 118.Objects may include, but are not limited to, items 104, users 116, totes118, and so forth. In another example, sensor data from an instrumentedauto-facing unit may be used to determine a quantity on hand at aparticular inventory location 114, change in quantity of items 104resulting from a pick or place, and so forth.

The facility 102 may be configured to receive different kinds of items104 from various suppliers and to store them until a customer orders orretrieves one or more of the items 104. A general flow of items 104through the facility 102 is indicated by the arrows of FIG. 1.Specifically, as illustrated in this example, items 104 may be receivedfrom one or more suppliers, such as manufacturers, distributors,wholesalers, and so forth, at the receiving area 106. In variousimplementations, the items 104 may include merchandise, commodities,perishables, or any suitable type of item 104, depending on the natureof the enterprise that operates the facility 102.

Upon being received from a supplier at the receiving area 106, the items104 may be prepared for storage in the storage area 108. For example, insome implementations, items 104 may be unpacked or otherwise rearranged.The inventory management system 122 may include one or more softwareapplications executing on a computer system to provide inventorymanagement functions. These inventory management functions may includemaintaining information indicative of the type, quantity, condition,cost, location, weight, or any other suitable parameters with respect tothe items 104. The items 104 may be stocked, managed, or dispensed interms of countable units, individual units, or multiple units, such aspackages, cartons, crates, pallets, or other suitable aggregations.Alternatively, some items 104, such as bulk products, commodities, andso forth, may be stored in continuous or arbitrarily divisible amountsthat may not be inherently organized into countable units. Such items104 may be managed in terms of measurable quantity such as units oflength, area, volume, weight, time, duration, or other dimensionalproperties characterized by units of measurement. Generally speaking, aquantity of an item 104 may refer to either a countable number ofindividual or aggregate units of an item 104 or a measurable amount ofan item 104, as appropriate.

After arriving through the receiving area 106, items 104 may be storedwithin the storage area 108. In some implementations, like items 104 maybe stored or displayed together in the inventory locations 114 such asin instrumented AFUs, bins, on shelves, hanging from pegboards, and soforth. In this implementation, all items 104 of a given kind are storedin one inventory location 114. In other implementations, like items 104may be stored in different inventory locations 114. For example, tooptimize retrieval of certain items 104 having frequent turnover withina large physical facility 102, those items 104 may be stored in severaldifferent inventory locations 114 to reduce congestion that might occurat a single inventory location 114.

When a customer order specifying one or more items 104 is received, oras a user 116 progresses through the facility 102, the correspondingitems 104 may be selected or “picked” from the inventory locations 114containing those items 104. In various implementations, item picking mayrange from manual to completely automated picking. For example, in oneimplementation, a user 116 may have a list of items 104 they desire andmay progress through the facility 102 picking items 104 from inventorylocations 114 within the storage area 108, and placing those items 104into a tote 118. In other implementations, employees of the facility 102may pick items 104 using written or electronic pick lists derived fromcustomer orders. These picked items 104 may be placed into the tote 118as the employee progresses through the facility 102.

After items 104 have been picked, they may be processed at a transitionarea 110. The transition area 110 may be any designated area within thefacility 102 where items 104 are transitioned from one location toanother or from one entity to another. For example, the transition area110 may be a packing station within the facility 102. When the item 104arrives at the transition area 110, the items 104 may be transitionedfrom the storage area 108 to the packing station. Information about thetransition may be maintained by the inventory management system 122.

In another example, if the items 104 are departing the facility 102, alist of the items 104 may be obtained and used by the inventorymanagement system 122 to transition responsibility for, or custody of,the items 104 from the facility 102 to another entity. For example, acarrier may accept the items 104 for transport with that carrieraccepting responsibility for the items 104 indicated in the list. Inanother example, a user 116 may purchase or rent the items 104 andremove the items 104 from the facility 102. During use of the facility102, the user 116 may move about the facility 102 to perform varioustasks, such as picking or placing the items 104 in the inventorylocations 114.

The inventory management system 122 may be configured to access physicallayout data 124, item data 126, or other information during operation.The physical layout data 124 comprises information such as thearrangement of inventory locations 114 and modular elements of themodular item stowage system, such as described below in more detail. Theitem data 126 may comprise information about one or more of the items104. The item data 126 may include, but is not limited to, weight of asingle item 104 (or package of items), physical dimensions of packaging,images of a single item 104 from different points of view, and so forth.The physical dimensions of the packaging may include height, width,depth, and so forth, of the single item 104, a package of items, orother unit. The item data 126 may also include information indicative ofa particular inventory location 114 at which the item 104 may be stowed,and so forth.

In some implementations, items 104 may be processed, such as at thereceiving area 106, to generate at least a portion of the item data 126.For example, an item 104 not previously stored by the inventorymanagement system 122 may be scanned or measured to determine thephysical dimensions as part of a process to receive the item 104 intothe facility 102. In another example, the receiving process at thefacility 102 may include receiving or accessing previously generatedinformation about the item 104. Continuing the example, an electronicmanifest record may include an item identifier, weight, physicaldimensions, and so forth.

The one or more sensors 120 may produce sensor data 128. For example,the cameras may produce image data, weight sensors may produce weightdata, instrumented AFUs may provide position data indicative of aposition of the sled or amount of displacement of the sled, and soforth.

The modular item stowage system may include one or more platforms 130.The platform 130 may be freestanding, mounted to a support structure,suspended from an overhead structure, and so forth. Each platform 130provides a structure to which one or more modular elements may becoupled. An overall shape of the platform 130 may be a rectangle. Inother implementations, the platform 130 may have an overall shape thatis a quadrilateral, triangle, hexagon, circle, or other polyhedron. Themodular elements may include, but are not limited to, instrumentedauto-facing units (AFUs) 132, dividers 134, spacers 136, and so forth.The platform 130 may provide one or more bays for holding processingcomponents such as sensor controllers, computing devices, and so forth.These bays may provide environment protection for the devices therein.The platform 130 may include one or more sensors 120. For example, theplatform 130 may include a plurality of weight sensors to generateweight data of a load supported by the platform 130. A controller maydetermine one or more first weight values from the weight measured bythe plurality of weight sensors. The controller may determine a changein weight of the load. The change in weight may be associated withmounting of an empty modular element to the platform 130. For example,the association may be based on a lookup table that compares the changein weight of the load with predetermined weights of different modularelements. When the change in weight matches one of the predeterminedweights within a threshold tolerance, the weight change may beassociated with the addition or removal of a particular type of modularelement. The controller may then determine one or more tare weightvalues of the load on the platform, such as including the empty modularelement which has been added or removed. Features of the platform 130are discussed in more detail below with regard to FIGS. 4-7.

A mechanical coupling may be maintained between the modular element andthe platform 130. For example, the platform 130 may provide physicalsupport to the modular element. The mechanical coupling may include theuse of one or more of mechanical engagement features, magnets, gravity,and so forth. For example, the modular element may rest atop theplatform 130 that supports it. In another example, the modular elementmay comprise an AFU 132 (instrumented or uninstrumented) having tabs toengage corresponding slots on the platform 130 and a magnet on the AFU132 to apply a magnetic force to hold the platform 130 and the AFU 132together.

The coupling between the modular element and the platform 130 mayinclude providing data communication, electrical power, and so forth,between the modular element and the platform 130. For example, theinstrumented AFU 132 may electrically couple to the platform 130 toreceive power for onboard electronics and provide sensor data 128. Inanother example, data may be transferred between the modular element andthe platform 130 optically, such as using optical waveguides, infraredtransmission, and so forth. The instrumented AFU 132 is discussed inmore detail below with regard to FIGS. 8-10.

The platforms 130 may be positioned throughout the facility 102 andreconfigured at will by an operator of the facility 102. For example,the platform 130 may be configured to use platform base supports tomount to a support member, such as a rack. Upon a particular platform130, various modular elements may be arranged in various permutations.For example, the platform 130 may be configured with AFUs 132alternating with dividers 134. The AFUs 132 are used to stow the items104 therein, while the dividers 134 maintain tidiness of the facility102 by constraining items 104 to a particular lane defined by theinventory location 114. The dividers 134 may comprise vertical walls.These vertical walls may divide the items held by a first modularelement from a second modular element. The walls may comprise one ormore of solid sheets, wire, slats, and so forth. The solid sheets maycomprise aluminum, steel, plastic, and so forth. The one or more wiresmay be straight or bent to form the vertical wall.

In some situations, the item 104 to be stowed may exceed the width ofthe AFU 132. In this situation, spacers 136 may be placed adjacent tothe AFU 132 to provide additional width for the item 104 to extend intoor over. As the needs of the facility 102 change, the modular elementsmay be added, removed, or rearranged to suit changing configurations ofitems 104 while the platform 130 is emplaced. For example, the modularelements on a platform 130 that is mounted to a support member may berearranged without removal of the platform 130 itself. The platforms 130may be added, removed, repositioned, and so forth, within the facility102. For example, a platform 130 may be removed or added to the supportmember without affecting neighboring platforms 130.

The modular elements may be configured to have a common sizing tofacilitate modular operation. A common depth (front-to-back length) ofthe modular elements may be used. The width of the modular elements mayvary as an integer multiple of a minimum size increment. Differentmodular elements may have different widths. For example, the minimumsize increment may be ⅓ inch with modular elements such as the AFUs 132,the dividers 134, and the spacers 136 available in widths such 1⅓ inch,2 inches, 2⅔ inches, and so forth.

By utilizing the modular item stowage system described, the facility 102may be easily configured to support different items 104, differentarrangements of items 104, and so forth. Furthermore, the sensors 120 inthe platform 130 and other modular elements provide sensor data 128 tothe inventory management system 122. This sensor data 128 may be used tomaintain information such as quantity of an item 104 picked, placed,currently on hand, and so forth.

FIG. 2 is a block diagram 200 illustrating additional details of thefacility 102, according to some implementations. The facility 102 may beconnected to one or more networks 202, which in turn connect to one ormore servers 204. The network 202 may include private networks such asan institutional or personal intranet, public networks such as theInternet, or a combination thereof. The network 202 may utilize wiredtechnologies (e.g., wires, fiber optic cables, and so forth), wirelesstechnologies (e.g., radio frequency, infrared, acoustic, optical, and soforth), or other connection technologies. The network 202 isrepresentative of any type of communication network, including one ormore of data networks or voice networks. The network 202 may beimplemented using a wired infrastructure (e.g., copper cable, fiberoptic cable, and so forth), a wireless infrastructure (e.g., cellular,microwave, satellite, and so forth), or other connection technologies.

The servers 204 may be configured to execute one or more modules orsoftware applications associated with the inventory management system122. While the servers 204 are illustrated as being in a locationoutside of the facility 102, in other implementations, at least aportion of the servers 204 may be located at the facility 102. Theservers 204 are discussed in more detail below with regard to FIG. 3.

The users 116, the totes 118, or other objects in the facility 102 maybe equipped with one or more tags 206. The tags 206 may be configured toemit a signal 208. In one implementation, the tag 206 may be a radiofrequency identification (RFID) tag configured to emit a RF signal 208upon activation by an external signal. For example, the external signalmay comprise a radio frequency signal or a magnetic field configured toenergize or activate the RFID tag 206. In another implementation, thetag 206 may comprise a transmitter and a power source configured topower the transmitter. For example, the tag 206 may comprise a BluetoothLow Energy (BLE) transmitter and battery. In other implementations, thetag 206 may use other techniques to indicate presence of the tag 206.For example, an acoustic tag 206 may be configured to generate anultrasonic signal 208, which is detected by corresponding acousticreceivers. In yet another implementation, the tag 206 may be configuredto emit an optical signal 208.

The inventory management system 122 may be configured to use the tags206 for one or more of identification of the object, determining alocation of the object, and so forth. For example, the users 116 maywear tags 206, the totes 118 may have tags 206 affixed, and so forth,which may be read and, based at least in part on signal strength, usedto determine identity and location.

Generally, the inventory management system 122 or other systemsassociated with the facility 102 may include any number and combinationof input components, output components, and servers 204.

The one or more sensors 120 may be arranged at one or more locationswithin the facility 102. For example, the sensors 120 may be mounted onor within a floor, wall, at a ceiling, at an inventory location 114, ona tote 118, may be carried or worn by a user 116, and so forth.

The sensors 120 may include one or more cameras 120(1). The one or morecameras 120(1) may include imaging sensors configured to acquire imagesof a scene. The imaging sensors are configured to detect light in one ormore wavelengths including, but not limited to, terahertz, infrared,visible, ultraviolet, and so forth. The imaging sensors may comprisecharge coupled devices (CCD), complementary metal oxide semiconductor(CMOS) devices, microbolometers, and so forth. The inventory managementsystem 122 may use image data acquired by the cameras 120(1) duringoperation of the facility 102. For example, the inventory managementsystem 122 may identify items 104, users 116, totes 118, and so forth,based at least in part on their appearance within the image dataacquired by the cameras 120(1). The cameras 120(1) may be mounted invarious locations within the facility 102. For example, cameras 120(1)may be mounted overhead, on inventory locations 114, and so forth.

One or more 3D sensors 120(2) may also be included in the sensors 120.The 3D sensors 120(2) are configured to acquire spatial or 3D data, suchas depth information, about objects within a field of view of a sensor120. The 3D sensors 120(2) include range cameras, lidar systems, sonarsystems, radar systems, structured light systems, stereo vision systems,optical interferometry systems, and so forth. The inventory managementsystem 122 may use the 3D data acquired by the 3D sensors 120(2) toidentify objects, determine a location of an object in 3D real space,and so forth.

One or more buttons 120(3) may be configured to accept input from theuser 116. The buttons 120(3) may comprise mechanical, capacitive,optical, or other mechanisms. For example, the buttons 120(3) maycomprise mechanical switches configured to accept an applied force froma touch of the user 116 to generate an input signal. The inventorymanagement system 122 may use data from the buttons 120(3) to receiveinformation from the user 116. For example, the tote 118 may beconfigured with a button 120(3) to accept input from the user 116 andsend information indicative of the input to the inventory managementsystem 122.

The sensors 120 may include one or more touch sensors 120(4). The touchsensors 120(4) may use resistive, capacitive, surface capacitance,projected capacitance, mutual capacitance, optical, InterpolatingForce-Sensitive Resistance (IFSR), or other mechanisms to determine theposition of a touch or near-touch. For example, the IFSR may comprise amaterial configured to change electrical resistance responsive to anapplied force. The location within the material of that change inelectrical resistance may indicate the position of the touch. Theinventory management system 122 may use data from the touch sensors120(4) to receive information from the user 116. For example, the touchsensor 120(4) may be integrated with the tote 118 to provide atouchscreen with which the user 116 may select from a menu of one ormore particular items 104 for picking, enter a manual count of items 104at an inventory location 114, and so forth.

One or more microphones 120(5) may be configured to acquire informationindicative of sound present in the environment. In some implementations,arrays of microphones 120(5) may be used. These arrays may implementbeamforming techniques to provide for directionality of gain. Theinventory management system 122 may use the one or more microphones120(5) to acquire information from acoustic tags 206, accept voice inputfrom the users 116, determine ambient noise level, and so forth.

One or more weight sensors 120(6) are configured to measure the weightof a load. For example, the platform 130 may include weight sensors120(6) to measure objects supported thereby, such as modular elements,items 104, and so forth. The weight sensors 120(6) may be configured tomeasure the weight of the load at the tote 118, on the floor of thefacility 102, and so forth. The weight sensors 120(6) may include one ormore sensing mechanisms to determine the weight of a load. These sensingmechanisms may include piezoresistive devices, piezoelectric devices,capacitive devices, electromagnetic devices, optical devices,potentiometric devices, microelectromechanical devices, and so forth.The sensing mechanisms of weight sensors 120(6) may operate astransducers that generate one or more signals based on an applied force,such as that of the load due to gravity. For example, the weight sensor120(6) may comprise a load cell having a strain gauge and a structuralmember that deforms slightly when weight is applied. By measuring achange in the electrical characteristic of the strain gauge, such ascapacitance or resistance, the weight may be determined. The inventorymanagement system 122 may use the data acquired by the weight sensors120(6), such as on the platform 130, to identify an object, determine achange in the quantity of objects, determine a location of an object,maintain shipping records, and so forth.

The sensors 120 may include one or more optical sensors 120(7). Theoptical sensors 120(7) may be configured to provide data indicative ofone or more of color or intensity of light impinging thereupon. Forexample, the optical sensor 120(7) may comprise a photodiode andassociated circuitry configured to generate a signal or data indicativeof an incident flux of photons. For example, the optical sensor 120(7)may comprise an ambient light sensor such as the ISL76683 as provided byIntersil Corporation of Milpitas, Calif., USA, or the MAX44009 asprovided by Maxim Integrated Products Inc. of San Jose, Calif., USA. Inother implementations, other optical sensors 120(7) may be used. Theoptical sensors 120(7) may be sensitive to one or more of infraredlight, visible light, or ultraviolet light. For example, the opticalsensors 120(7) may be sensitive to infrared light.

The optical sensors 120(7) may include photodiodes, photoresistors,photovoltaic cells, quantum dot photoconductors, bolometers,pyroelectric infrared detectors, and so forth. For example, the opticalsensor 120(7) may use germanium photodiodes to detect infrared light. Insome implementations, the optical sensors 120(7) may be arranged in atwo dimensional array (such as rows and columns) and mounted beneath,above, or to the side of an inventory location 114. For example, thearray may be below the AFU 132, incorporated into a spacer 136, and soforth. The sensor data 128 from the array may be used to detect shadowscast by the items 104, users 116, and so forth. This information may beused by the inventory management system 122 to track objects, determineinteractions with items 104, and so forth.

One or more radio frequency identification (RFID) readers 120(8), nearfield communication (NFC) systems, and so forth, may be included assensors 120. For example, the RFID readers 120(8) may be configured toread the RF tags 206. Information acquired by the RFID reader 120(8) maybe used by the inventory management system 122 to identify an objectassociated with the RF tag 206 such as the item 104, the user 116, thetote 118, and so forth. For example, based on information from the RFIDreaders 120(8) detecting the RF tag 206 at different times and RFIDreaders 120(8) having different locations in the facility 102, avelocity of the RF tag 206 may be determined.

One or more RF receivers 120(9) may also be included as sensors 120. Insome implementations, the RF receivers 120(9) may be part of transceiverassemblies. The RF receivers 120(9) may be configured to acquire RFsignals 208 associated with Wi-Fi, Bluetooth, ZigBee, 3G, 4G, LTE, orother wireless data transmission technologies. The RF receivers 120(9)may provide information associated with data transmitted via radiofrequencies, signal strength of RF signals 208, and so forth. Forexample, information from the RF receivers 120(9) may be used by theinventory management system 122 to determine a location of an RF source,such as a communication interface onboard the tote 118.

The sensors 120 may include one or more accelerometers 120(10), whichmay be worn or carried by the user 116, mounted to the tote 118, and soforth. The accelerometers 120(10) may provide information such as thedirection and magnitude of an imposed acceleration. Data such as rate ofacceleration, determination of changes in direction, speed, and soforth, may be determined using the accelerometers 120(10).

A gyroscope 120(11) may provide information indicative of rotation of anobject affixed thereto. For example, the tote 118 or other objects maybe equipped with a gyroscope 120(11) to provide data indicative of achange in orientation of the object.

A magnetometer 120(12) may be used to determine an orientation bymeasuring ambient magnetic fields, such as the terrestrial magneticfield. The magnetometer 120(12) may be worn or carried by the user 116,mounted to the tote 118, and so forth. For example, the magnetometer120(12) mounted to the tote 118 may act as a compass and provideinformation indicative of which direction the tote 118 is oriented.

A position sensor 120(13) provides information indicative of a positionof an object. In one implementation, the position sensor 120(13) may beincorporated into the instrumented AFU 132 to provide information abouta position of one or more of items 104, a sled of the instrumented AFU132, a position target on the sled, and so forth. The position sensor120(13) may use optical, magnetic, capacitive, inductive, resonantinductive, resistive, ultrasonic, or other techniques to determinepresence of an object. For example, the position sensor 120(13) maycomprise an ultrasonic transducer to determine a distance to a portionof the sled. In another example, the position sensor 120(13) maycomprise a linear potentiometer or string potentiometer that measuresposition or displacement of an object based on a change in electricalresistance. The position sensor 120(13) may report a value as one ormore of an analog signal or a digital signal. For example, a value ofthe amplitude of an analog signal such as the electrical resistance ofthe linear potentiometer may be indicative of the position. A digitalsignal may be indicative of the position. For example, the position maybe expressed as an 8 bit value. In some implementations, the positionsensor 120(13) may include a controller to generate sensor data 128indicative of the position or displacement of the object. For example,the controller may determine a linear measurement in inches or metersbased on the amplitude of the analog signal, the 8 bit value, and soforth. The position sensor 120(13) is discussed in more detail belowwith regard to FIG. 9.

The sensors 120 may include other sensors 120(S) as well. For example,the other sensors 120(S) may include proximity sensors, ultrasonicrangefinders, thermometers, barometric sensors, hygrometers, and soforth. For example, the inventory management system 122 may useinformation acquired from thermometers and hygrometers in the facility102 to direct the user 116 to check on delicate items 104 stored in aparticular inventory location 114, which is overheating, too dry, toodamp, and so forth.

In some implementations, the camera 120(1) or other sensors 120 mayinclude hardware processors, memory, and other elements configured toperform various functions. For example, the cameras 120(1) may beconfigured to generate image data, send the image data to another devicesuch as the server 204, and so forth.

The facility 102 may include one or more access points 210 configured toestablish one or more wireless networks. The access points 210 may useWi-Fi™, NFC, Bluetooth®, or other technologies to establish wirelesscommunications between a device and the network 202. The wirelessnetworks allow the devices to communicate with one or more of thesensors 120, the inventory management system 122, the tag 206, acommunication device of the tote 118, or other devices.

Output devices 212 may also be provided in the facility 102. The outputdevices 212 are configured to generate signals, which may be perceivedby the user 116 or detected by the sensors 120. In some implementations,the output devices 212 may be used to provide illumination of theoptical sensor array.

Haptic output devices 212(1) are configured to provide a signal thatresults in a tactile sensation to the user 116. The haptic outputdevices 212(1) may use one or more mechanisms such as electricalstimulation or mechanical displacement to provide the signal. Forexample, the haptic output devices 212(1) may be configured to generatea modulated electrical signal, which produces an apparent tactilesensation in one or more fingers of the user 116. In another example,the haptic output devices 212(1) may comprise piezoelectric or rotarymotor devices configured to provide a vibration, which may be felt bythe user 116.

One or more audio output devices 212(2) may be configured to provideacoustic output. The acoustic output includes one or more of infrasonicsound, audible sound, or ultrasonic sound. The audio output devices212(2) may use one or more mechanisms to generate the acoustic output.These mechanisms may include, but are not limited to, the following:voice coils, piezoelectric elements, magnetorestrictive elements,electrostatic elements, and so forth. For example, a piezoelectricbuzzer or a speaker may be used to provide acoustic output.

The display devices 212(3) may be configured to provide output, whichmay be seen by the user 116 or detected by a light-sensitive sensor suchas a camera 120(1) or an optical sensor 120(7). In some implementations,the display devices 212(3) may be configured to produce output in one ormore of infrared, visible, or ultraviolet light. The output may bemonochrome or color.

The display devices 212(3) may be emissive, reflective, or both. Anemissive display device 212(3), such as using light emitting diodes(LEDs), is configured to emit light during operation. In comparison, areflective display device 212(3), such as using an electrophoreticelement, relies on ambient light to present an image. Backlights orfront lights may be used to illuminate non-emissive display devices212(3) to provide visibility of the output in conditions where theambient light levels are low.

The display devices 212(3) may include, but are not limited to,microelectromechanical systems (MEMS), spatial light modulators,electroluminescent displays, quantum dot displays, liquid crystal onsilicon (LCOS) displays, cholesteric displays, interferometric displays,liquid crystal displays (LCDs), electrophoretic displays, and so forth.For example, the display device 212(3) may use a light source and anarray of MEMS-controlled mirrors to selectively direct light from thelight source to produce an image. These display mechanisms may beconfigured to emit light, modulate incident light emitted from anothersource, or both. The display devices 212(3) may operate as panels,projectors, and so forth.

The display devices 212(3) may be configured to present images. Forexample, the display device 212(3) may comprise an addressable display212(3)(1). The addressable display 212(3)(1) may comprise elements thatmay be independently addressable to produce output, such as pixels. Forexample, the addressable display 212(3)(1) may produce an image using atwo-dimensional array of pixels.

In some implementations, the display devices 212(3) may be configured toprovide non-image data, such as text characters, colors, and so forth.For example, an addressable display 212(3)(1) may comprise a segmentedelectrophoretic display device 212(3), segmented LED, and so forth, andmay be used to present information such as a stock keeping unit (SKU)number, quantity on hand, and so forth. The display devices 212(3) mayalso be configurable to vary the color of the segment, such as usingmulticolor/multi-wavelength LED segments.

The display devices 212(3) may include image projectors 212(3)(2). Forexample, the image projector 212(3)(2) may be configured to project animage onto objects, illuminate at least a portion of an optical sensorarray, and so forth. The image may be generated using MEMS, LCOS, and soforth.

The display devices 212(3) may include a light array 212(3)(3). Thelight array 212(3)(3) may comprise a plurality of discrete emissiveelements configurable to emit light. The discrete emissive elements (orassemblies thereof) may be separated from one another by a distance suchthat, when image data of the light array 212(3)(3) is acquired, oneemissive element may be distinguished from another. For example, thelight array 212(3)(3) may comprise a plurality of infrared LEDsseparated by at least 0.5 centimeters.

Other display devices 212(3)(D) may also be used in the facility 102.The display devices 212(3) may be located at various points within thefacility 102. For example, the addressable displays 212(3)(1) or thelight arrays 212(3)(3) may be located on inventory locations 114, totes118, in or on the floor of the facility 102, and so forth.

Other output devices 212(P) may also be present. For example, the otheroutput devices 212(P) may include scent/odor dispensers, documentprinters, 3D printers or fabrication equipment, and so forth.

FIG. 3 illustrates a block diagram 300 of a server 204 configured tosupport operation of the facility 102, according to someimplementations. The server 204 may be physically present at thefacility 102, may be accessible by the network 202, or a combination ofboth. The server 204 does not require end-user knowledge of the physicallocation and configuration of the system that delivers the services.Common expressions associated with the server 204 may include “on-demandcomputing”, “software as a service (SaaS)”, “platform computing”,“network-accessible platform”, “cloud services”, “data centers”, and soforth. Services provided by the server 204 may be distributed across oneor more physical or virtual devices.

One or more power supplies 302 may be configured to provide electricalpower suitable for operating the components in the server 204. The oneor more power supplies 302 may comprise batteries, capacitors, fuelcells, photovoltaic cells, wireless power receivers, conductivecouplings suitable for attachment to an external power source such asprovided by an electric utility, and so forth. The server 204 mayinclude one or more hardware processors 304 (processors) configured toexecute one or more stored instructions. The processors 304 may compriseone or more cores. One or more clocks 306 may provide informationindicative of date, time, ticks, and so forth. For example, theprocessor 304 may use data from the clock 306 to associate a particularinteraction with a particular point in time.

The server 204 may include one or more communication interfaces 308 suchas input/output (I/O) interfaces 310, network interfaces 312, and soforth. The communication interfaces 308 enable the server 204, orcomponents thereof, to communicate with other devices or components. Thecommunication interfaces 308 may include one or more I/O interfaces 310.The I/O interfaces 310 may comprise Inter-Integrated Circuit (I2C),Serial Peripheral Interface bus (SPI), Universal Serial Bus (USB) aspromulgated by the USB Implementers Forum, RS-232, and so forth.

The I/O interface(s) 310 may couple to one or more I/O devices 314. TheI/O devices 314 may include input devices such as one or more of asensor 120, keyboard, mouse, scanner, and so forth. The I/O devices 314may also include output devices 212 such as one or more of a displaydevice 212(3), printer, audio speakers, and so forth. In someembodiments, the I/O devices 314 may be physically incorporated with theserver 204 or may be externally placed.

The network interfaces 312 may be configured to provide communicationsbetween the server 204 and other devices, such as the totes 118,routers, access points 210, and so forth. The network interfaces 312 mayinclude devices configured to couple to personal area networks (PANs),local area networks (LANs), wide area networks (WANs), and so forth. Forexample, the network interfaces 312 may include devices compatible withEthernet, Wi-Fi, Bluetooth, ZigBee, and so forth.

The server 204 may also include one or more busses or other internalcommunications hardware or software that allow for the transfer of databetween the various modules and components of the server 204.

As shown in FIG. 3, the server 204 includes one or more memories 316.The memory 316 may comprise one or more non-transitory computer-readablestorage media (CRSM). The CRSM may be any one or more of an electronicstorage medium, a magnetic storage medium, an optical storage medium, aquantum storage medium, a mechanical computer storage medium, and soforth. The memory 316 provides storage of computer-readableinstructions, data structures, program modules, and other data for theoperation of the server 204. A few example functional modules are shownstored in the memory 316, although the same functionality mayalternatively be implemented in hardware, firmware, or as a system on achip (SoC).

The memory 316 may include at least one operating system (OS) module318. The OS module 318 is configured to manage hardware resource devicessuch as the I/O interfaces 310, the I/O devices 314, the communicationinterfaces 308, and provide various services to applications or modulesexecuting on the processors 304. The OS module 318 may implement avariant of the FreeBSD operating system as promulgated by the FreeBSDProject; other UNIX or UNIX-like variants; a variation of the Linuxoperating system as promulgated by Linus Torvalds; the Windows operatingsystem from Microsoft Corporation of Redmond, Wash., USA; and so forth.

Also stored in the memory 316 may be a data store 320 and one or more ofthe following modules. These modules may be executed as foregroundapplications, background tasks, daemons, and so forth. The data store320 may use a flat file, database, linked list, tree, executable code,script, or other data structure to store information. In someimplementations, the data store 320 or a portion of the data store 320may be distributed across one or more other devices including theservers 204, network attached storage devices, and so forth.

A communication module 322 may be configured to establish communicationswith one or more of the totes 118, sensors 120, display devices 212(3),other servers 204, or other devices. The communications may beauthenticated, encrypted, and so forth.

The memory 316 may store an inventory management module 324. Theinventory management module 324 is configured to provide the inventoryfunctions as described herein with regard to the inventory managementsystem 122. For example, the inventory management module 324 may trackitems 104 between different inventory locations 114, to and from thetotes 118, and so forth.

The inventory management module 324 may include one or more of a dataacquisition module 326 or a processing module 328. The data acquisitionmodule 326 may be configured to acquire and access informationassociated with operation of the facility 102. For example, the dataacquisition module 326 may be configured to acquire sensor data 128 fromone or more sensors 120. This information may be stored in the datastore 320.

The processing module 328 may be configured to process the sensor data128 to generate information such as a quantity of items 104 at aninventory location 114, change in quantity over time, and so forth. Theprocessing module 328 may utilize or more of the physical layout data124, item data 126, or threshold data 330 during operation. Thethreshold data 330 may specify one or more thresholds, such aspermissible tolerances or variances. For example, the thresholds mayspecify a percentage variance between an estimated change in positionbased on item data 126 and change in quantity and a measured change inposition measured by the position sensor 120(13).

The processing module 328 may be configured to process the sensor data128 from the weight sensors 120(6). For example, the sensor data 128from the weight sensors 120(6) may be used to determine a change inquantity, determine where from upon the platform 130 an item 104 wasremoved, and so forth. In another example, the processing module 328 mayaccess the sensor data 128 acquired by the instrumented AFU 132(27). Thesensor data 128 from the position sensor 120(13) may indicate a linearchange in position of a sled of the instrumented AFU 132(27) of 3.2inches. The processing module 328 may access the physical layout data124 to determine that instrumented AFU 132(27) is used to store item104(114) described as “canned dog food”. The physical characteristicsfor the item 104(114) may be retrieved from the item data 126,indicating a per-item depth of 3 inches for each can of dog food. Theprocessing module 328 may divide the linear change in position by theper-item depth to generate a measured count of quantity change.Continuing the example, 3.2/3=1.07. The quotient may be rounded toproduce a result that a quantity of 1 of item 104(114) was removed fromthe instrumented AFU 132(27). As a result, the inventory managementmodule 324 may decrease the quantity of the item 104(114) stored atinstrumented AFU 132(27) by 1.

In some implementations, the processing module 328 may use sensor data128, such as image data obtained from the cameras 120(1), to determineproximity of the user 116 to the inventory location 114 that includesthe instrumented AFU 132. As a result, a quantity associated with theuser 116 may be changed based on the sensor data 128 obtained from theinstrumented AFU 132. Continuing the example, a quantity of 1 of theitem 104(114) may be added to a manifest or order pick list associatedwith the user 116.

Processing of the sensor data 128 or other data may be performed by theprocessing module 328 or other modules implementing at least in partusing the OpenCV library as developed by Intel Corporation of SantaClara, Calif., USA; Willow Garage of Menlo Park, Calif., USA; and Itseezof Nizhny Novgorod, Russia, with information available atwww.opencv.org. In another implementation, functions available in theOKAO machine vision library as promulgated by Omron Corporation ofKyoto, Japan, may be used to process the sensor data 128.

Techniques such as artificial neural networks (ANN), active appearancemodels (AAM), active shape models (ASM), principal component analysis(PCA), cascade classifiers, and so forth, may also be used to processthe sensor data 128 or other data. For example, the ANN may be a trainedusing a supervised learning algorithm such that object identifiers areassociated with images of particular objects within training imagesprovided to the ANN. Once trained, the ANN may be provided with thesensor data 128 such as the image data from a camera 120(1), and mayprovide, as output, the object identifier.

Other modules 334 may also be present in the memory 316 as well as otherdata 336 in the data store 320. For example, the other modules 334 mayinclude an accounting module while the other data 336 may includebilling data. The accounting module may be configured to assess chargesto accounts associated with particular users 116 or other entities,while the billing data may include information such as payment accountnumbers.

Modular Item Stowage Hardware

Features in the following figures are depicted for purposes ofillustration and not necessarily as limitations. The figures are not toscale.

FIG. 4 illustrates a side view 400 of inventory locations 114 comprisingthe platforms 130, according to some implementations. As specified by anoperator of the facility 102, the inventory location 114 may include agroup of platforms 130 (such as an entire rack), an individual platform130, or the discrete locations for storage of items 104 therein, such asthe AFUs 132, bins, hangers, and so forth. Two AFUs 132 are depictedmounted to two of the platforms 130 in this illustration.

A support member 402 provides a structure to which one or more platformbase supports 404 may be affixed. For example, the support member 402may comprise an upright member with slots or other mechanical engagementfeatures. The slots or other mechanical engagement features may beregularly spaced. The platform base supports 404 may be able tomechanically engage the support member 402 and the platform 130. In someimplementations, the platform base supports 404 may be integral orotherwise affixed to the platform 130. For example, hooks or othermechanical engagement features may extend from a back of the platform130. In this illustration, the support member 402 is depicted aspositioned to the back of the platform 130. In other implementations,the support member 402 may be in different positions relative to theplatforms 130. For example, the support member 402 may support theplatform 130 from a front of the platform 130, where the front isproximate to the location of a user 116 during typical use of picking orplacing items 104.

The support member 402 may be vertical, at an angle to vertical, orhorizontal. For example, the support member 402 may comprise ahorizontal rail supported by legs. In other implementations, the supportmember 402 may suspend one or more platforms 130 from an overheadstructure.

A plurality of platforms 130 may be supported from one or more of thesupport members 402. The support member 402 may provide for one or moreof horizontal or vertical separation between platforms 130. For example,a first platform 130(1) may be above a second platform 130(2),side-by-side, and so forth.

A cable management system 406 may be provided to guide cablingconnecting the platforms 130 to other devices. For example, the cablemanagement system 406 may route cabling between the platform 130 andEthernet switches, power supplies, and so forth. In someimplementations, integrated busses, cabling, electrical conductors,optical waveguides, and so forth, may be integrated into the supportmember(s) 402.

In other implementations, a system may be provided for thermalmanagement of the platforms 130 and the devices therein. For example,ductwork or piping may be provided to move a working fluid such as airor water through the platform 130 to remove heat dissipated during theoperation of the electronics therein. Continuing the example, the cablemanagement system 406 may incorporate ducts to deliver cool air to theplatform 130 and remove warm air from the platform 130.

The cabling integrated into the support member(s) 402 may also providethe physical media for communication of the network 202, or a portionthereof. For example, the platform 130 may send sensor data 128 to theinventory management module 324 executing on one or more of the servers204. The inventory management module 324 or another module may alsocommunicate with one or more of the devices onboard the platform 130.For example, the inventory management module 324 may provideconfiguration information to a computing device onboard the platform130, the instrumented AFU 132, and so forth. In other implementations,wireless power transfer, wireless data transfer, and so forth, may beused instead of, or in addition to, the cabling. For example, a wirelessaccess point, NFC transceiver, or other devices may be incorporated intothe support member 402.

One or more cameras 120(1) are positioned within the facility 102. Eachcamera 120(1) has a field of view (FOV) 408. Cameras 120(1) may bearranged within the facility 102 to have a FOV 408 that includes atleast a portion of one or more of the inventory locations 114. Forexample, a camera 120(1) may be mounted overhead in the facility 102,such as from the ceiling. In another example, the camera 120(1) may bemounted above a platform 130 with the FOV 408 oriented to where theitems 104 may be stowed during use.

FIG. 5 illustrates two views 500 of a platform 130. A first view 502depicts the platform 130 in an unpopulated configuration, such as beforemodular elements have been affixed. A second view 504 depicts theplatform 130 in a populated configuration, in which a plurality ofmodular elements such as AFUs 132, dividers 134, spacers 136, and soforth, have been coupled to the platform 130.

The platform 130 includes a shelf base 506. The shelf base 506 maycomprise an upper portion of the platform 130. For example, the shelfbase 506 may comprise stainless steel that has been powder coated. Insome implementations, the shelf base 506 may have a predominantly planarconfiguration, describing a flat surface upon which one or more of themodular elements may rest, or be positioned immediately above. The shelfbase 506 may have a first elevation at a first height. Within at least aportion of the shelf base 506, a cable recess 508 may be provided.

Located beneath the shelf base 506 may be a plurality of weight sensors120(6). For example, the location of the weight sensors 120(6)(1) and120(6)(2) under a left side of the shelf base 506 are indicated by adotted outline. A cutaway view shows the weight sensors 120(6)(3) and120(6)(4) under a right side of the shelf base 506. The plurality ofweight sensors 120(6) may provide sensor data 128 such as weight of aload on the shelf base 506, weight distribution of the load, and soforth. The configuration of the weight sensors 120(6) in the platform130 are described in more detail below with regard to FIG. 7.

The weight distribution provides information indicative of weightapplied to weight sensors 120(6) at different points under the load.Sensor data 128 from a plurality of weight sensors 120(6) may becombined. For example, the weights from the weight sensors 120(6)(1) and120(6)(2) may be summed to provide a weight measured at a left side ofthe platform, and weights from the weight sensors 120(6)(3) and120(6)(4) may be summed to provide a weight measured at a right side ofthe platform 130. The weight distribution may be expressed as a measuredweight at a particular weight sensor 120(6), a ratio or percentage ofweight on a weight sensor 120(6), and so forth. For example, the weightdistribution data may be expressed as “3213 g left, 2214 g right”, as adimensionless ratio such as “0.59 left, 0.41 right”, and so forth.

The cable recess 508 has a second elevation that is lower than the firstelevation. In this illustration the second elevation may bedistinguished from the first elevation by different crosshatch patterns.In some implementations, the shelf base 506 and the cable recess 508 maybe a single piece of material or may be several pieces of materialjoined together, such as by welding, riveting, adhesives, fasteners, andso forth.

The cable recess 508 provides a volume for routing cabling that connectselectronics within the platform 130 to one or more of the modularelements, such as the instrumented AFU 132. The cable recess 508 may bearranged around one or more of the weight sensors 120(6). For example,in this illustration, the cable recess 508 includes two incursions orpeninsulas to allow for placement of the weight sensors 120(6)(2) and120(6)(4) beneath the shelf base 506. In this illustration, the cablerecess 508 describes a contiguous area. However, in otherimplementations, the cable recess 508 may comprise separate compartmentsor sections. For example, the shelf base 506 may include a plurality ofcable recesses 508. The cable recess 508 may be arranged generallytowards the front of the shelf base 506. For example, the cable recess508 may be arranged in a front third of the distance from the front tothe back of the shelf base 506 and extending across the width of theshelf base 506.

Within the cable recess 508 may be one or more drains 510. The drains510 provide a path for spilled liquids to exit the cable recess 508. Forexample, the instrumented AFU 132 above the cable recess 508 may holdcontainers of bottled water. Should one of the containers leak, thedrain 510 prevents accumulation of the water.

Also arranged within the cable recess 508 are one or more connectors512. The connectors 512 are configured to couple to components in one ormore of the modular elements. In one implementation, the connectors 512may comprise connectors utilizing the RJ-45 form factor. The connectors512 may be rated to the Ingress Protection (IP) standards IP67 or IP68as described by the International Electrotechnical Commission (IEC) inspecification IEC 60529.

A front lip 514 is arranged along a front of the platform 130. In someimplementations, the front lip 514 may comprise an extension or portionof the shelf base 506 and may share a common elevation with the shelfbase 506. In other implementations, the front lip 514 may be at adifferent elevation, such as above or below the elevation of the shelfbase 506.

The front lip 514 may include one or more front engagement features 516.A plurality of front engagement features 516 may be arranged atpredetermined spacing intervals with respect to one another along thefront lip 514. The front engagement features 516 may include, but arenot limited to, one or more of the following: slots, recesses, tabs,hooks, latches, rails, lips, ferrous material, hook and loop fasteners,and so forth. For example, the front lip 514 may include a steel member.The front engagement features 516 may be able to accept and mechanicallyengage corresponding features on the front of the modular element.

A slot may comprise an opening in another material. For example, theslot may comprise a hole that has a rectangular, square, elliptical, orother shape. A hook may comprise a member having an asymmetrical shape.For example, a hook may have a shaft with a barb or tip that protrudesperpendicular to a long axis of the hook. The barb or top maymechanically engage a corresponding engagement feature on anothermember. A tab may comprise a member that protrudes from anotherstructure. In some implementations the tab may have a ridge or otherengagement feature that may mechanically engage a corresponding featureon another member. A bar may comprise a member that has a cross-sectionthat is generally a parallelogram. A rod may comprise a member that isarcuate in cross-section, such as circular or elliptical. A tube maycomprise a member that has a cross-section that is generally aparallelogram, arcuate in cross-section, and so forth. For example, thetube may have a circular cross-section.

The engagement features may use magnetic forces to engage two or moremembers. For example, a magnet may be attracted to another magnet,attracted to a ferromagnetic material, repelled from another magnet, andso forth. The ferromagnetic material may include, but is not limited to,iron, nickel, cobalt, neodymium, and so forth.

In one implementation, the front engagement features 516 may compriseindexing slots. The indexing slots may be oriented vertically such thatthe corresponding indexing features from a modular element may beinserted from above. For example, the AFU 132 (instrumented oruninstrumented) may include one or more indexing features such as tabsor pegs that slide into the front engagement feature 516 uponinstallation. For example, an indexing tab may extend from the AFU 132to engage the front engagement feature. The front engagement features516 may be configured to provide lateral stability, preventing themodular element from shifting left to right along the width of theplatform 130. In some implementations, the front engagement features 516may not provide for vertical engagement with the indexing features. Forexample, an indexing feature of the AFU 132 may not “catch” or otherwisebe restrained from vertical motion by the front engagement feature 516.

In some implementations, the front lip 514 may incorporate one or moreferrous materials that are attractive to a magnet. In someimplementations, the front lip 514 may incorporate one or more magnets.As described below, the magnets may be used to secure the AFU 132 orother modular elements after installation on the platform 130. Themagnets may be used to maintain vertical engagement, maintaining a pullbetween a front of the modular element and the front lip 514. In otherimplementations, nonmagnetic techniques may be used to retain the frontof the modular element to the front lip 514 during operation whilemaintaining the ability to remove the modular element. For example, ahook and loop fastener, low-tack pressure sensitive adhesive, suctioncups, vacuum clamps, and so forth, may be used instead of or in additionto magnets.

Arranged from left to right along the back of the shelf base 506 may beone or more back engagement features 518. The back engagement features518 may be part of a back wall, extending vertically from a back portionof the shelf base 506. A plurality of back engagement features 518 maybe arranged at regularly spaced intervals with respect to one anotheralong the back of the shelf base 506. The back engagement features 518may include, but are not limited to, one or more of the following:slots, recesses, tabs, hooks, latches, rails, lips, hook and loopfasteners, and so forth. The back engagement features 518 may behorizontally accessible, that is a corresponding feature from a modularelement may be inserted in a generally horizontal motion if the shelfbase 506 is substantially flat with respect to the Earth. For example,the back engagement features 518 may comprise slots in a back wallextending vertically upward from the shelf base 506, the slots having alongest axis that is perpendicular to a plane described by the shelfbase 506. An angle between the back wall and the shelf base 506 may be,within a threshold tolerance, a right angle. The back engagementfeatures 518 may be able to accept and mechanically engage correspondingfeatures on the back of the modular element. For example, the AFU 132may have tabs that engage the slots.

In some implementations, the back engagement feature 518 may compriseone or more bars, rods, or other members. The modular element may beconfigured to engage at least a portion of this member. For example, themodular element may be suspended in a cantilever fashion from the backengagement feature 518.

The platform 130 may include one or more internal electronics bays 520.The internal electronics bay 520 may be arranged under the shelf base506. A perimeter of the internal electronics bay 520 is presented inthis illustration as a dotted line. The internal electronics bay 520 maycomprise one or more devices. For example, the internal electronics bay520 may contain one or more of the controllers or other electronicsassociated with the weight sensors 120(6), one or more computingdevices, and so forth. One or more cable harnesses provide communicationbetween the connectors 512 and one or more of the devices within theinternal electronics bay 520. The internal electronics bay 520 isdescribed in more detail below with regard to FIG. 6.

One or more platform base supports 404 may also be provided. Asdescribed above, platform base supports 404 may be integral with orotherwise part of the platform 130. In some implementations, platformbase supports 404 may include a platform base upon which the platform130 may rest. For example, the shelf base 506, modular elements affixedthereto, and so forth, may be supported from the platform base by theweight sensors 120(6). In some implementations, the internal electronicsbay 520 may rest on the platform base or may be mounted to the shelfbase 506.

Also depicted in this illustration are cross-sectional lines. A crosssection along line A-A is described below with regard to FIG. 6. A crosssection along line B-B is described below with regard to FIG. 7.

In a populated second view 504 depicted in this illustration, a numberof different modular elements have been affixed to the platform 130. Forexample, several AFUs 132 have been installed. This installation mayinclude the connection of a data cable (not shown) from the instrumentedAFU 132 to one or more of the connectors 512. Adjacent to the AFUs 132may be dividers 134. The dividers 134 may comprise vertical membersextending upwards such as walls that act as partitions between adjacentmodular elements. In some implementations, modular elements mayincorporate built-in walls or partitions. In another implementation, thedivider 134 may comprise wire, tubing, or other features to direct theitems 104. For example, the divider 134 may comprise one or more bentwires. To accommodate items 104 that have a width exceeding that of theAFU 132, or to hold items 104 without the use of an AFU 132, a spacer136 may be employed. To accommodate larger items 104, two or more AFUs132 may be placed adjacent to one another or may be separated by one ormore spacers 136. In some implementations, the two or more AFUs 132 maybe instrumented, or one may be instrumented and the othernon-instrumented.

The surface of the modular elements may utilize one or more of textures,coatings, or features to facilitate movement of items 104. For example,linear ridge features extending from the front to the back of themodular element may be used to reduce friction between the items 104 andthe surface of the modular element to facilitate sliding of the items104.

The modular elements may be configured to have a common sizing tofacilitate the modular operation. A common depth (front-to-back length)of the modular elements may be used. For example, each of the modularelements may have the same depth dimension.

The width of the modular elements may vary. In some implementations,modular elements may vary in width as an integer multiple of a minimumsize increment. For example, the minimum size increment may be ⅓ inchwith modular elements such as the AFUs 132, the dividers 134, and thespacers 136 available in widths such 1⅓ inch, 2 inches, 2⅔ inches, andso forth.

In other implementations, other modular elements may be used. Forexample, the other modular elements may include bins, dispensers,hangers, hooks, and so forth.

While the platform 130 has been described in terms of a structure uponwhich the load such as the modular elements sits, in otherimplementations, the modular elements may be suspended from the platform130. For example, the platform 130 may support a plurality of hangerrods or pegs, from which one or more items 104 depend.

FIG. 6 illustrates a side view 600 of the platform 130 along line A-A,according to some implementations.

The platform 130 may include one or more spill diverters 602. The spilldiverter 602 may comprise one or more physical features such as a lip,ridge, trough, and so forth, that divert spills of liquids or solidsaway from one or more of the connectors 512. For example, as illustratedin FIG. 6, the spill diverter 602 comprises an overhang extending awayfrom a vertical face to which the connector 512 is mounted, partiallyinto the cable recess 508 above the connector 512. The extent of theoverhang by the spill diverter 602 into the cable recess 508 may be lessthan, equal to, or greater than the portion of the connector 512 withinthe cable recess 508. In some implementations, the spill diverter 602may be contiguous across the width of the shelf base 506 proximate tothe cable recess 508. In other implementations, the spill diverter 602may comprise a plurality of separate features, such as discrete ridgeswith each ridge associated with a particular connector 512. The spilldiverter 602 may be arranged such that a spilled liquid is directedtowards one or more of the drains 510.

The internal electronics bay 520 provides a volume within whichelectronics may be protected from the environment around the platform130. For example, the internal electronics bay 520 may provideprotection from moisture, fluids, dust, and so forth. In someimplementations, the internal electronics bay 520 may providetemperature control as well. For example, where the platform 130 isdeployed into a refrigerated area, the internal electronics bay 520 mayinclude a heater to maintain a minimum acceptable temperature of thedevices within the internal electronics bay 520.

Devices within the internal electronics bay 520 may be accessed by oneor more removable access panels 604. In the implementation depictedhere, the access panel 604 is arranged along an underside of theplatform 130. The access panel 604 may be secured to the platform 130using one or more mechanical fasteners, latches, magnets, interferencefit, and so forth. A seal 606 may be arranged around the interface orjunction between a plurality of bay walls 608 and the access panel 604.For example, the seal 606 may comprise silicone rubber, room temperaturevulcanizing rubber, and so forth.

The bay walls 608, in conjunction with the access panel 604 (when inplace), encompass a sealed volume of the internal electronics bay 520.This sealed volume within the internal electronics bay 520 preventscontaminants such as dust, moisture, and so forth, from affecting thecontents of the internal electronics bay 520. Points of entry for cableharnesses or other cabling into the internal electronics bay 520 may besealed as well.

In some implementations, the bay walls 608 may comprise a portion of theplatform 130 structure itself. For example, the shelf base 506 and oneor more of the bay walls 608 may be the same piece of material.

As described above, the platform 130 may have elements at differentelevations. Depicted here is the shelf base 506 at a first elevation610. Also depicted is a second elevation 612 of the cable recess 508. Asshown, the second elevation 612 of the cable recess 508 is lower thanthe first elevation 610 of the shelf base 506. While the cable recess508 is depicted with a flat bottom, in other implementations, othercross sectional shapes may be used. For example, the cable recess 508may slant downwards from underneath the connector 512 towards the lowestpoint of the second elevation 612.

A front stop 614 is also shown as part of the platform 130. The frontstop 614 may be positioned in front of the front lip 514, such as on aside of the front lip 514 opposite the cable recess 508. The front stop614 may comprise a removable piece that is retained in place duringnormal use by a front stop retainer 616. The front stop retainer 616 maybe secured to the platform 130 using one or more mechanical fasteners,latches, magnets, interference fit, and so forth. For example, threadedbolts or screws may be used to hold the front stop retainer 616 to theplatform 130. The front stop 614 may comprise a plate or planar piece ofrigid or semi-rigid material. The front stop 614 may help retain items104 within the modular elements. For example, the front stop 614 mayprevent the items 104 held by the AFU 132 from being pushed off of theAFU 132 and onto the floor below. In some implementations, the frontstop 614 or another structure may be configured to support one or morelabels, tags, or other displays for presenting information to the users116 of the facility 102.

One or more lights 620 may be arranged on an underside of the platform130. These lights 620 may include LEDs, incandescent lights, fluorescentlights, electroluminescent lights, quantum dots, lasers, and so forth.The lights 620 may provide illumination for objects below the platform130. For example, the lights 620 may illuminate items 104 on the modularelements below. The lights 620 may be positioned proximate to the frontof the platform 130. The lights 620 may be configured to direct emittedlight, such as down and towards the back of the inventory location 114below, such as another platform 130. The lights 620 may include opticalelements such as reflectors, lenses, light pipes, and so forth, toprovide desired illumination.

FIG. 7 illustrates a side view of the platform 130 along line B-B,according to some implementations. Along the line B-B are the weightsensors 120(6)(1) and 120(6)(2) arranged underneath the shelf base 506.In the implementation depicted here, an internal support structure 702is depicted that provides support between the shelf base 506 and theweight sensors 120(6). For example, the internal support structure 702may comprise one or more “C” channel rails that support the shelf base506 and transfer a mechanical load from the shelf base 506 to the weightsensors 120(6). In some implementations the internal support structure702 may be optional. For example, the weight sensors 120(6) may directlysupport the shelf base 506.

The platform 130 may rest upon a platform base 704. For example, theplatform base 704 may be affixed to the platform base supports 404.Continuing the example, the platform base 704 and a platform basesupports 404 may comprise a shelf upon which the platform 130 rests. Theweight sensors 120(6) act as an interface between the platform 130 andthe platform base 704, transferring the weight of the platform 130 and aload thereupon to the platform base 704.

The weight sensors 120(6) may include a load cell 706. The load cell 706may include a load cell body 708. The load cell body 708 may comprise astructure or material that, under the influence of an applied force suchas the weight of a load thereupon, will deflect or bend. In someimplementations, such as shown here, cutouts or voids may be providedwithin the load cell body 708. The load cell body 708 may include, orhave affixed thereto, a transducer such as a strain gauge to measure theextent of the deflection. In other implementations, the load cell body708 itself may comprise a transducer material such that distortion ordeflection due to an imposed load generates a detectable signal that maybe used to determine an applied weight.

One or more mounting features 710 may be used to retain the load cell706 to the platform 130 and the platform base 704. For example, themounting feature 710 may include one or more pins, bolts, threadedsockets, and so forth. Continuing the example, a mounting feature 710 onthe underside of the load cell 706 at the interface between the loadcell 706 and the platform base 704 may comprise a foot to rest upon theplatform base 704 or a bolt to pass through the corresponding hole inthe platform base 704 and be retained with a nut.

A spacer 712 having a thickness 714 is placed between the load cell 706and the corresponding mating surface of the platform 130. The mountingfeature 710 such as a bolt or pin through the spacer 712 may maintainthe position of the spacer 712 and also affix the load cell 706 to theplatform 130.

The spacer 712 provides a gap or standoff between the load cell 706 andthe rest of the platform 130. For example, the spacer 712 may be used tomaintain a gap of thickness 714 between a top of the load cell 706 andthe bottom of the internal support structure 702 when the platform 130is in a base load or unpopulated state. The spacer 712 may comprise aseparate piece, such as a discrete piece of metal, plastic, ceramic, andso forth. In other implementations, the load cell body 708 may beformed, machined, or otherwise designed such that the spacer 712 isintegrated thereto. For example, a first end of the load cell body 708may be stepped or thicker than a second end. During use, as modularelements and items 104 are added to the platform 130, the weight on theplatform 130 and on the respective load cells 706 increases.

The thickness 714 of the spacer 712 may be configured such thatoverloading the platform 130 with too much weight will result in theload cell 706 “bottoming out” before there is irreparable damage to theload cell body 708 or the other components of the load cell 706. Forexample, the load cell 706 may be described as having two load supportareas 716. A first load support area 716(1) of each load cell 706 ispositioned medially, that is on an end of the load cell 706 that isclosest to the neighboring load cell 706. The first load support area716(1) may be the point at which a mounting feature 710 and the spacer712 transfer the weight of a load from the platform 130 to the load cell706. A second load support area 716(2) is distal from the first loadsupport areas 716(1) and the neighboring load cell 706. The second loadsupport area 716(2) transfers the weight of the load from the load cell716 to the platform base 704.

During normal operation, the weight of the load on the load cell 706such as the weight of the platform 130 and any modular elementsthereupon is applied to the first load support area 716(1). The loadcell body 708 may undergo a slight deformation or change in shape thatis detectable and may be used to determine a numeric value of theweight. The force of the weight then passes through the load cell body708 to the second load support area 716(2) and onto the platform base704. During an overload condition, the upper surface of the load cellbody 708 at the second load support area 716(2) may come in contact withthe internal support structure 702, shelf base 506, or other structureto which the upper mounting feature 710 of the load cell 706 is affixed.The thickness 714 of the spacer 712 allows sufficient travel for thedistal end of the load cell body 708 to be displaced, provide formeasurement of a desired range of weights, while preventing excessivetravel that may result in irreparable damage to the load cell 706. Thespacer 712 that provides a safety mechanism to avoid damaging load cell706 should a user 116 inadvertently overload the platform 130.

In other implementations, other configurations of load cell 706 may beused. For example, the load cell 706 may be configured as a single-endedbeam, double-ended beam, S-beam, and so forth.

The weight sensors 120(6) may be readily accessible and fieldreplaceable. For example, weight sensors 120(6) incorporating load cells706 having different weight ranges or capacities may be readily changedout to accommodate different types of loads. Continuing the example,where the platform 130 will be supporting modular elements holding items104 that are heavy such as canned foods, load cells 706 and spacers 712designed for the estimated total load of the platform 130 may beinstalled in the platform 130. In comparison, where the platform 130will be supporting items 104 that are lighter, such as potato chips,different load cells 706 and spacers 712 may be installed in theplatform 130. The weight sensors 120(6) may be selected to provide aparticular operating range such as a minimum weight, maximum weight,desired weight resolution, and so forth, as desired by operators of thefacility 102.

FIG. 8 illustrates top views 800 of an instrumented AFU 132, accordingto some implementations. The AFU 132 may be instrumented to providesensor data 128 that may be used to determine information such asquantity of items 104 held by the instrumented AFU 132.

The AFU 132 may include an AFU base 802. One or more items 104 that maybe stowed by the AFU 132 may sit upon the AFU base 802. One or morerails 804 may be integral with, or affixed to, the AFU base 802. Forexample, two rails 804 may be used as illustrated here, with each rail804 on an opposite side of the AFU base 802.

A front clip 806 is arranged at a front of the AFU base 802 proximate toa front end of the rails 804. As described below in more detail, thefront clip 806 may constrain the travel of the sled towards the front ofthe AFU base 802. The front clip 806 may have one or more mechanicalengagement features that retain the front clip 806 to the AFU base 802.For example, the front clip 806 may have one or more ridges or tabs thatengage corresponding slots within the AFU base 802.

A back clip 808 is arranged at a back of the AFU base 802 proximate to abackend of the rails 804. As described below in more detail, the backclip 808 may constrain the travel of the sled towards the back of theAFU base 802. The back clip 808 may have one or more mechanicalengagement features that retain the back clip 808 to the AFU base 802.For example, the back clip 808 may have one or more ridges or tabs thatengage corresponding slots within the AFU base 802.

Extending from a back of the AFU base 802 or other portion of the AFU132 may be one or more AFU back engagement features 810. The AFU backengagement features 810 are configured to engage one or more of the backengagement features 518 of the platform 130. In some implementations,the AFU back engagement features 810 may extend from the back of the AFU132.

A sled 812 comprises an assembly that is movable relative to the AFUbase 802. The sled 812 may include one or more features that are engagedby the rail 804. The sled 812 may travel linearly from front to back ofthe AFU base 812 as constrained by the front clip 806 and the back clip808. The one or more rails 804 retain the sled 812 with respect to theAFU base 802.

The sled 812 may include a pushplate 814, an actuator 816, and theposition target 818. The pushplate 814 comprises a member that comes incontact with one or more items 104 that may be stowed by the AFU 132.The pushplate 814 may comprise a member having a substantially flat,curvilinear, or other shape with a long axis generally perpendicular tothe AFU base 802.

The actuator 816 may comprise one or more of a spring or motor. In thisillustration, the actuator 816 is depicted as being located on the sled812. In other implementations, the actuator 816 may be positioned withinAFU base 802, the front clip 806, or another portion of the AFU 132. Theactuator 816 is configured to apply a force 820 to the sled 812 suchthat the sled 812 is biased to move towards the front clip 806. Theactuator 816 may comprise a linear motor, rotary motor, and so forth.For example, a linear or rotary motor may be used to move the sled 812towards or away from the front of the AFU base 802.

The force 820 provided by the actuator 816 may be sufficient to push oneor more of the items 104 that are on the AFU base 802 towards the frontstop 614. For example, the actuator 816 may comprise a variable forcespring with one end attached to the sled 812 and the other attached toone or more of the front of the AFU base 802 or the front clip 806. Inone implementation, a portion of the variable force spring may be bent,with the bent portion engaging a portion of the front clip 806, such asan edge of a slot. In another implementation, the variable force springmay be riveted, screwed, glued, laminated, or otherwise affixed to thefront clip 806.

Under the influence of the actuator 816 that produces the force 820, asitems 104 are added to or removed from the AFU base 802, the sled 812moves towards or away from the front clip 806. Position data may begenerated by a position sensor 120(13) within the instrumented AFU 132that is indicative of a position 822 of the sled 812. The position 822may be relative to a particular origin or a reference point on theinstrumented AFU 132, such as the rearmost portion of the back clip 808as illustrated here. In other implementations, other origins orreference points may be used, such as a front of the AFU base 802,relative to the position sensor 120(13) itself, and so forth. Theposition 822 and the corresponding position data may be represented interms of a binary value, absolute measurement, and so forth. Forexample, the position 822 may be represented as a four bit value,distance in inches, and so forth.

In this illustration, at time=1, three items 104 are shown stored by theinstrumented AFU 132. For example, the position 822(1) is indicative offirst position data such as “1 inch”. At time=2, one item 104 has beenremoved, leaving two items 104 still stowed by the instrumented AFU 132.As a result of the force 820 applied by the actuator 816, the sled 812has moved to a new position 822(2). Continuing the example, the position822(2) is indicative of second position data such as “4 inches”. Thecontroller device onboard the instrumented AFU 132, or another devicesuch as the server 204, may process sensor data 128 indicative of one ormore of the first position 822(1), the second position 822(2), or adifference between the two (such as “+3 inches”). Based on the sensordata 128 providing information about one or more of the change inposition 822, the magnitude of the change in position 822, the sign ofthe change in position 822, speed of change in position 822, and soforth, information indicative of an interaction with the items 104stowed by the instrumented AFU 132 may be determined. For example, basedon the change in position of 3 inches, the item data 126 indicative ofthe depth of the type of item 104 stowed by the instrumented AFU 132being 3 inches each, and a positive sign of the difference, theprocessing module 328 may determine that a quantity of one of the items104 stowed by the AFU 132 has been picked.

The position target 818 is detectable by a position sensor locatedwithin or underneath the AFU base 802. The position target 818 maycomprise an active or passive component. An active component may use abattery or electrical energy received via wires to generate a signal.For example, an infrared emitter is an active component. In comparison,a passive component may interact with a signal produced by detector. Forexample, passive component may comprise an inductive target. Theposition target 818 and its interaction with the position sensor 120(13)are discussed in more detail below with regard to FIG. 9.

While the AFU 132 is described in terms of discrete components, in someimplementations, a single structure may be used instead of discretecomponents. For example, the front clip 806, the rails 804, the AFU base802, and the back clip 808 may comprise a single piece or structure thatis formed, milled, or otherwise fabricated. Likewise, the sled 812 maycomprise a single piece or structure.

FIG. 9 illustrates side views 900 of different versions of theinstrumented AFUs 132, according to some implementations. At 902, anactive force mechanism version of the instrumented AFU 132 is depicted.At 904, a gravity feed version of the instrumented AFU 132 is depicted.As FIG. 9 depicts different versions of the instrumented AFUs 132,portions of the platform 130, such as the front stop 614, are notpresented.

With regard to the active force mechanism version at 902, severalfeatures are designed to assist in the mounting of the AFU 132 to theplatform 130. One or more engagement features such as magnets 906 may beplaced proximate to a front end of the AFU base 802. The one or moremagnets 906 may be located on an underside of the AFU base 802, on anupper side of the AFU base 802, or within the AFU base 802. Wheninstalled at the platform 130, the magnet 906 is attracted to a ferrousmaterial or another magnet positioned within the front lip 514. Theattraction of the magnet 906 to the front lip 514 or other portion ofthe shelf base 506 provides a force to retain the AFU base 802 inposition, with respect to the shelf base 506, during use. For example,as a user 116 pushed to insert or remove items 104 from the AFU 132, themagnet 906 keeps the front of the AFU base 802 from tipping upwards.

In other implementations, other engagement features including, but notlimited to, hook and loop fasteners, low-tack pressure sensitiveadhesives, suction cups, vacuum clamps, a portion of a spring from theactuator 816, and so forth, may be used instead of or in addition tomagnets 906. For example, a portion of the spring from the actuator 816may have one or more bends or features therein that are configured toengage into a corresponding engagement feature in the front lip 514.Continuing the example, the front end of the spring from the actuator816 may be bent to form a ridge that may then engage a slot within thefront lip 514. The magnet 906 or other mechanism provides a force thatretains the front of the AFU 132 in contact with the front lip 514.

One or more front indexing features 908 may be proximate to the front ofthe AFU 132. In some implementations, one or more of the front indexingfeatures 908 may extend from or be integral with the front clip 806. Thefront indexing feature 908, when engaged with the front engagementfeatures 516 of the front lip 514, may be configured to provide lateralstability to prevent the AFU 132 from shifting left to right along thewidth of the platform 130. The front indexing feature 908 may comprise amember extending downwards perpendicularly from the front of the AFUbase 802, the front clip 806, or another portion of the AFU 132. In someimplementations, the front indexing feature 908 may not provide forvertical engagement with the indexing features. For example, the frontindexing feature 908 may comprise a smooth sided tab of a constant crosssection. When engaged, the front indexing feature 908 prevents lateralmotion of the front end of the AFU 132.

One or more position sensors 120(13) may be incorporated into theinstrumented AFU 132. The position sensor 120(13) provides informationindicative of a position of one or more of items 104, the sled 812, theposition target 818 held by the sled 812, and so forth. The positionsensor 120(13) may use optical, magnetic, capacitive, inductive, orother techniques to determine presence of an object. For example, theposition sensor 120(13) may comprise a resonant inductive positionsensor such as the 205 mm Type 6.8 Linear Sensor provided by CambridgeIntegrated Circuits Ltd. Of Cambridge, United Kingdom. This positionsensor uses a plurality of sensor coils mounted to a printed circuitboard that detect the presence of an inductive resonator that acts asthe position target 818. For example, the position target 818 maycomprise an inductive resonator element, such as a coil, having aresonant frequency. The position sensor 120(13) may include an excitercoil to generate a magnetic field at the resonant frequency. Theposition sensor 120(13) may also include a plurality of sensor coils.During operation, the exciter coil emits a magnetic field that inducesan electromotive force (EMF) in the inductive resonator element. ThisEMF then produces a signal that may be detected by sensor coils. Aprocessor or controller may then determine proximity of the positiontarget based on strength of the signal at the plurality of sensor coils,and given the known location of and distance between the sensor coils.The processor may then generate sensor data 128 indicative of therelative position of the sled 812.

In one implementation, the position sensor 120(13) may comprise a lineararray of inductive sensors. The inductive sensors may be configured toemit an electromagnetic signal that interacts with the position target818. When a particular inductive sensor of the linear array detects asignal corresponding to position target 818, the position 822 may bedetermined as corresponding to that of the particular inductive sensor.In another implementation, the position sensor 120(13) may comprise alinear array of Hall effect sensors or other sensors able to detect amagnetic field. The position target 818 may comprise a magnet, with themagnetic field produced by that magnet detectable by the sensors in thelinear array. In yet another implementation, the position sensor 120(13)may comprise optical emitters, optical transmitters, and so forth. Forexample, an infrared LED may provide illumination while infraredphotodiodes are used to detect a particular light pattern reflected bythe position target 818, underside of the sled 812, and so forth.

In other implementations, an active portion of the position sensor120(13) may be located on the sled 812. For example, opticallydetectable targets such as a barcode may be printed on or otherwisearranged on an upper surface of the AFU base 802. An optical transceivercomprising an infrared LED and an infrared photodiode may be configuredto detect the barcode and determine position information based oninformation encoded therein. In another implementation, anoptoelectronic sensor comprising a low-resolution two-dimensional arrayof monochromatic detectors and a light emitter may be used to detectmotion and distance traveled. It is recognized that a wide variety ofother mechanisms may be used to measure the relative displacement of thesled 812 with respect to the AFU base 802.

A data cable 910 that is terminated in a plug 912 may be used to couplethe electronics of the position sensor 120(13) to one or more of theconnectors 512 within the cable recess 508 of the platform 130. The datacable 910 may be used to transfer the sensor data 128 to an externaldevice, such as a computing device in the platform 130. The data cable910 may exit the AFU base 802 in approximately a front half or frontthird of the AFU base 802. For example, the exit point for the datacable 910 from the AFU base 802 may be arranged to correspond with thecable recess 508 when the instrumented AFU 132 is installed onto theplatform 132.

In some implementations, the data cable 910 may be omitted, and aconnector 512 may be provided within the front lip 514. In such animplementation, the cable recess 508 may be omitted from the platform130. In other implementations, the data cable 910 or similar physicalinterconnects may be omitted. For example, the position sensor 120(13)may provide the resulting sensor data 128 wirelessly. The components ofthe position sensor 120(13) that use electrical power may receive powerwirelessly. In other implementations, power may be provided from one ormore conductive rails or features arranged at one or more of the frontlip 514, such as within the front engagement features 516, the backengagement feature 518, and so forth. In yet another implementation, theposition sensor 120(13) or other components of the instrumented AFU 132may be powered by batteries, capacitors, photovoltaic cells,thermocouples, kinetic energy harvesting devices, and so forth. Forexample, movement of the sled 812 may be used to generate electricalenergy that powers the position sensor 120(13) or other components.

While the modular element may couple to the connectors 512 in the shelfbase 506, in some implementations the modular elements may bedaisy-chained. For example, a first data cable 910 of a first modularelement may connect to a connector on a second modular element. Thesecond modular element may then connect to one of the connectors 512using a second data cable 910. The first modular element may perform oneor more data processing functions, or may pass through any signals ordata between the devices in the shelf base 506 and the second modularelement.

In some implementations, one or more of the components within theinstrumented AFU 132 may be sealed or held in place using a pottingcompound. For example, epoxy may be placed within the AFU base 802 toseal and retain components such as the position sensor 120(13), themagnet 906, a portion of the data cable 910, and so forth. Portions ofthe AFU base 802 or other components may include integrated featuressuch as ridges that are produced during manufacture. These features mayact as dams to retain the potting compound while in its liquid stateduring manufacture.

With regard to the gravity feed version 904, the actuator 816 may beomitted. Instead, a tilt support 914 may maintain the AFU base 802 at anangle. For example, the AFU base 802 may have a first elevation at thefront and a second elevation at the back, with the second elevationbeing higher than the first elevation. The AFU base 802 may include oneor more rollers 916 to facilitate movement of the items 104 towards afront of the AFU base 802. The weight of the items 104 and the weight ofthe sled 812 may provide the force 820 in this version. In someimplementations of this version, the sled 812 may include additionalmass to increase the force 820.

FIG. 10 illustrates a side view 1000 of the sled 812 of the instrumentedAFU 132, according to some implementations. As described above, the sled812 may include a pushplate 814, an actuator 816, and a position target818. These components may be mounted or otherwise secured to a sled base1002. The sled base 1002 may include one or more rail engagementfeatures 1004. The rail engagement features 1004 assist in maintainingthe sled 812 proximate to the AFU base 802 during operation. The railengagement features 1004 may comprise ridges or protrusions thatmechanically engage one or more sides of the rails 804. For example, theridges may mechanically engage an upper face and a lower face of therails 804. The rail engagement features 1004 in combination with therails 804 may constrain motion of the sled 812 along a single axis.

In this illustration, the actuator 816 comprises spring 1006. Forexample, the spring 1006 may comprise a stainless steel spring havingone end affixed to a portion of the sled 812 and the other end affixedto the front of the AFU base 802 or the front clip 806. In someimplementations, the spring 1006 may engage a front of the AFU base 802and the front clip 806 may hold the spring 1006 in place to maintainthat engagement. In some implementations, the spring 1006 may bedismountable from the front clip 806. By being readily dismountable,such as without tools or with simple tools, changing of springs 1006that have become worn or broken is performed more easily. Spring 1006may also be changed to provide a different level of force 820 at the AFU132, and so forth. For example, an AFU 132 holding heavy items 104 mayneed a more forceful spring 1006 than another AFU 132 holdinglightweight items 104.

In other implementations, the actuator 816 may be arranged in otherpositions. For example, the actuator 816 may be located within the AFUbase 802, within or affixed to the platform 130, and so forth.

One or more pushplate supports 1008 extend from the sled base 1002 tothe pushplate 814. The sled base 1002, the pushplate support 1008, andthe pushplate 814 may comprise one or more different mechanicalelements. For example, a single structure may be formed thatincorporates all three elements.

The pushplate support 1008 may be configured to maintain a front edge ofthe pushplate 1012 at a point which is forward of a front edge of thesled 1010. During operation of the AFU 132, if the front stop 614 isremoved, the front edge of the pushplate 1012 may extend the past thefront clip 806. Said another way, if the front clip 806 is removed, thespring 1006 and the arrangement of the front edge of the pushplate 1012may be such that all items 104 that are stowed by the AFU 132 would bepushed clear of the AFU base 802 and onto the floor.

In some implementations, the pushplate 814 may be removable or may haveadditional elements affixed thereto. For example, the pushplate 814 maybe removable from the pushplate support 1008 to enable use of apushplate 814 that has a larger area, smaller area, particular contour,particular height, particular width, and so forth. For example, a largepushplate 814 may be installed to the pushplate support 1008 toaccommodate bulky products.

The other modular elements may include one or more of the featuresdescribed above with regard to the AFU 132. For example, the dividers134, spacers 136, or other modular elements may include engagementfeatures, particular surface textures or treatments, and so forth.

Other implementations may be used in the facility 102. For example, themagnet 906 may be proximate to the back of the modular element ratherthan the front, and the various engagement features may be flipped tocorrespond. Continuing the example, the indexing feature may bepositioned at the back of the AFU 132, while engagement features arelocated at the front of the AFU 132.

In some implementations, the position sensors 120(13) may be within theplatform 130. For example, a plurality of position sensors 120(13) maybe arranged in lanes. A modular unit may then be attached to theplatform 130. In one variation of this implementation, the platform 130may include a shelf base 506 configured with engagement features to holdother elements, such as the sled 812. For example, the shelf base 506may include a plurality of rails 804 or similar features onto which thesled 812 may be engaged at a desired location. The position sensors120(13) in the platform 130 may determine the position of a sled 812 orposition target 818 therein.

The processes discussed herein may be implemented in hardware, software,or a combination thereof. In the context of software, the describedoperations represent computer-executable instructions stored on one ormore non-transitory computer-readable storage media that, when executedby one or more processors, perform the recited operations. Generally,computer-executable instructions include routines, programs, objects,components, data structures, and the like that perform particularfunctions or implement particular abstract data types. Those havingordinary skill in the art will readily recognize that certain steps oroperations illustrated in the figures above may be eliminated, combined,or performed in an alternate order. Any steps or operations may beperformed serially or in parallel. Furthermore, the order in which theoperations are described is not intended to be construed as alimitation.

Embodiments may be provided as a software program or computer programproduct including a non-transitory computer-readable storage mediumhaving stored thereon instructions (in compressed or uncompressed form)that may be used to program a computer (or other electronic device) toperform processes or methods described herein. The computer-readablestorage medium may be one or more of an electronic storage medium, amagnetic storage medium, an optical storage medium, a quantum storagemedium, and so forth. For example, the computer-readable storage mediamay include, but is not limited to, hard drives, floppy diskettes,optical disks, read-only memories (ROMs), random access memories (RAMs),erasable programmable ROMs (EPROMs), electrically erasable programmableROMs (EEPROMs), flash memory, magnetic or optical cards, solid-statememory devices, or other types of physical media suitable for storingelectronic instructions. Further, embodiments may also be provided as acomputer program product including a transitory machine-readable signal(in compressed or uncompressed form). Examples of transitorymachine-readable signals, whether modulated using a carrier orunmodulated, include, but are not limited to, signals that a computersystem or machine hosting or running a computer program can beconfigured to access, including signals transferred by one or morenetworks. For example, the transitory machine-readable signal maycomprise transmission of software by the Internet.

Separate instances of these programs can be executed on or distributedacross any number of separate computer systems. Thus, although certainsteps have been described as being performed by certain devices,software programs, processes, or entities, this need not be the case,and a variety of alternative implementations will be understood by thosehaving ordinary skill in the art. Additionally, those having ordinaryskill in the art readily recognize that the techniques described abovecan be utilized in a variety of devices, environments, and situations.

Although the subject matter has been described in language specific tostructural features or methodological acts, it is to be understood thatthe subject matter defined in the appended claims is not necessarilylimited to the specific features or acts described. Rather, the specificfeatures and acts are disclosed as illustrative forms of implementingthe claims.

What is claimed is:
 1. A platform comprising: a flat shelf base with afront and a back at a first elevation; a cable recess arranged proximateto the front of the flat shelf base and with a second elevation belowthe first elevation; a plurality of electrical connectors arrangedwithin the cable recess; the flat shelf base further including a frontlip arranged in front of the cable recess and at the first elevation; aplurality of front engagement slots within the front lip arranged at afirst predetermined spacing relative to one another; a plurality of backengagement slots arranged proximate to the back of the flat shelf baseand at a second predetermined spacing relative to one another; aplurality of weight sensors supporting the flat shelf base to generateweight data indicative of a load on the flat shelf base; and an internalelectronics bay beneath the flat shelf base.
 2. The platform of claim 1,each of the plurality of weight sensors further comprising: a load cellhaving a first end and a second end; and a spacer arranged at the firstend of the load cell between an upper surface of the load cell and alower surface of one or more of the flat shelf base or an internalsupport structure coupled to the flat shelf base, wherein a thickness ofthe spacer is configured to prevent excess travel of the load cell inthe event the load exceeds a threshold value.
 3. The platform of claim1, further comprising: a back wall extending vertically from a backportion of the flat shelf base, wherein an angle between the back walland the flat shelf base is approximately equal to a right angle; whereinthe plurality of back engagement slots are arranged within the backwall; and wherein the plurality of front engagement slots are arrangedwithin the flat shelf base proximate to the front.
 4. The platform ofclaim 1, the internal electronics bay further comprising: a plurality ofbay walls with an opening, the plurality of bay walls encompassing avolume; a removable access panel to close the opening; and a seal at aninterface between the plurality of bay walls and the removable accesspanel.
 5. An apparatus comprising: a flat shelf base with a front and aback at a first elevation; a cable recess arranged between the front andthe back and at a second elevation below the first elevation; aplurality of data connectors within the cable recess; a spill diverterarranged at an elevation above at least one of the plurality of dataconnectors; and a plurality of weight sensors, supporting the flat shelfbase, to generate weight data indicative of a load on the flat shelfbase.
 6. The apparatus of claim 5, further comprising: a front stopretainer that is removable and coupled, using one or more fasteners,proximate to the front of the flat shelf base; and a removable frontstop comprising a plate arranged between a portion of the flat shelfbase and the front stop retainer.
 7. The apparatus of claim 5, furthercomprising: a platform base upon which the plurality of weight sensorsrest; and one or more platform base supports coupled to the platformbase, wherein each of the one or more platform base supports includesone or more mechanical features to couple to a support member.
 8. Theapparatus of claim 5, wherein: the spill diverter comprises an overhangextending away from a face to which the plurality of data connectors aremounted.
 9. The apparatus of claim 5, wherein each of the plurality ofweight sensors comprises: a load cell having a plurality of load supportareas; and a spacer arranged between at least one of the plurality ofload support areas and the load.
 10. The apparatus of claim 5, the flatshelf base further comprising a front lip including one or more of aferrous material or a magnetic material.
 11. The apparatus of claim 5,further comprising: a plurality of front engagement features within afront lip arranged at a predetermined spacing relative to one another,the plurality of front engagement features comprising one or more of aslot, a tab, a hook, a ferrous material, or a magnet.
 12. The apparatusof claim 5, further comprising: a plurality of back engagement featuresarranged proximate to the back of the flat shelf base and at apredetermined spacing relative to one another, the plurality of backengagement features comprising one or more of a slot, a tab, a hook, aferrous material, or a magnet.
 13. The apparatus of claim 5, furthercomprising: beneath the flat shelf base, a plurality of bay walls toform an internal bay having an opening on an underside that is oppositethe flat shelf base; a removable access panel to close the opening; anda seal at an interface between at least a portion of the plurality ofbay walls and the removable access panel.
 14. An apparatus comprising: ashelf base with a front and a back; a cable recess inset to the shelfbase and accessible from above; one or more connectors within the cablerecess; a plurality of weight sensors to support the shelf base; aplatform base supporting the plurality of weight sensors; and one ormore platform base supports coupled to the platform base, the one ormore platform base supports including mechanical features to couple toan external support.
 15. The apparatus of claim 14, further comprising:a front lip of one or more of a ferrous material or a magnetic material;a first plurality of slots accessible from above, the first plurality ofslots within the front lip arranged at a first predetermined spacingrelative to one another; and a second plurality of slots arranged withina back wall of the shelf base and at a second predetermined spacingrelative to one another.
 16. The apparatus of claim 14, furthercomprising: a plurality of back engagement features arranged proximateto the back of the shelf base and at a predetermined spacing relative toone another, the plurality of back engagement features comprising one ormore of a slot, a tab, a hook, a ferrous material, or a magnet.
 17. Theapparatus of claim 14, further comprising: a front lip proximate to thefront of the shelf base; a removable front stop retainer coupledproximate to the front lip; and a removable front stop arranged betweena portion of the shelf base and the front stop retainer.
 18. Theapparatus of claim 14, wherein each of the plurality of weight sensorscomprises: a load cell having a plurality of load support areas; and aspacer arranged between at least one of the plurality of load supportareas and a load.
 19. The apparatus of claim 14, further comprising: aninternal electronics bay including: a plurality of bay walls; aremovable access panel; and one or more seals.
 20. The apparatus ofclaim 14, further comprising: a spill diverter extending at leastpartially over at least a portion of the one or more connectors.